In-situ slurry formation and delivery apparatus and method

ABSTRACT

An embodiment of the presently claimed invention includes an in-situ slurry formation apparatus mounted to die casting machines to convert liquid metal to semi-solid metal (SSM). Thus, there is no need to modify existing machines or change the cell layout to accommodate more space than would otherwise be necessary. These machines also need not be replaced with machines specially designed for SSM. Further, a method for converting molten metal to semi-solid metal includes coupling a conduit to a die casting machine, wherein the conduit comprises an inlet, an outlet and a body disposed between the inlet and the outlet, regulating the conduit&#39;s temperature, surrounding the conduit with a housing, inserting molten metal at the inlet, cooling the molten metal to semi-solid metal in the body, and expelling semi-solid metal from the outlet.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional patent applicationentitled, IN SITU SLURRY FORMATION AND DELIVERY TO DIE CAST MACHINES,filed Aug. 23, 2005, having a Ser. No. of 60/710,165, the disclosure ofwhich is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to casting metal alloys. Moreparticularly, the present invention relates to semi-solid metal casting.

BACKGROUND OF THE INVENTION

Casting complex geometries may yield products with undesirable shrinkporosity, which can adversely impact the quality and integrity of thecast part. Shrink porosity defines a condition that arises as a metalpart begins to shrink as it cools and solidifies along the outersurface, leaving pockets of air (referred to as “voids”) trapped in thecenter of the part. If the voids are not reconstituted with the metal,the cast part is termed “porous.” This condition is prevalent with theuse of aluminum alloys as the casting material.

Semi-solid metal casting (SSM) may be used to address this problem ofporosity in cast products, particularly for aluminum alloys. Advantagesto SSM casting include producing high quality parts with structuralintegrity, rigidity, strength and ductility.

As such, it is desirable to use SSM methods as often as feasible.Therefore, it is desirable to provide a mechanism to allow die castingmachines the ability to use SSM metals without replacing them orundergoing costly modifications to existing machines.

SUMMARY OF THE INVENTION

The foregoing needs are met, to a great extent, by the presentinvention, wherein in one aspect an apparatus is provided that in someembodiments a mechanism to allow die casting machines the ability to useSSM metals without replacing them or undergoing costly modifications toexisting machines.

In accordance with one embodiment of the present invention, an apparatusfor converting molten metal to semi-solid metal includes a conduithaving an inlet and an outlet to transport the molten metal, and atemperature regulator disposed adjacent the conduit to regulate thetemperature of the molten metal, and a housing surrounding the conduitand the temperature regulator.

In accordance with another embodiment of the present invention, a methodfor converting molten metal to semi-solid metal includes coupling aconduit to a die casting machine, wherein the conduit comprises aninlet, an outlet and a body disposed between the inlet and the outlet,regulating the conduit's temperature, surrounding the conduit with ahousing, inserting molten metal at the inlet, cooling the molten metalto semi-solid metal in the body, and expelling semi-solid metal from theoutlet.

In accordance with yet another embodiment of the present invention, asystem for converting molten metal to semi-solid metal includes meansfor coupling a conduit to a die casting machine, wherein the conduitcomprises an inlet, an outlet and a body disposed between the inlet andthe outlet, means for regulating the conduit's temperature, means forsurrounding the conduit with a housing, and means for cooling the moltenmetal to semi-solid metal in the body.

There has thus been outlined, rather broadly, certain embodiments of theinvention in order that the detailed description thereof herein may bebetter understood, and in order that the present contribution to the artmay be better appreciated. There are, of course, additional embodimentsof the invention that will be described below and which will form thesubject matter of the claims appended hereto.

In this respect, before explaining at least one embodiment of theinvention in detail, it is to be understood that the invention is notlimited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of embodiments inaddition to those described and of being practiced and carried out invarious ways. Also, it is to be understood that the phraseology andterminology employed herein, as well as the abstract, are for thepurpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conceptionupon which this disclosure is based may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present invention. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of an in-situ slurry formation apparatusaccording to an embodiment of the present invention.

FIG. 2 is an illustration of a HPDC die casting machine having thein-situ slurry formation apparatus incorporated therein.

FIG. 3 is a detailed representation of the in-situ slurry formationapparatus configured for the HPDC machine of FIG. 2.

FIG. 4 is a representation of a HVSC die casting machine having thein-situ slurry formation apparatus incorporated therein.

FIG. 5 is a detailed representation of the in-situ slurry formationapparatus configured for the HVSC machine of FIG. 4.

FIG. 6 is an illustration of the microstructure obtained for a 356alloy.

FIG. 7 is an illustration of the microstructure obtained for a 206alloy.

DETAILED DESCRIPTION

The foregoing needs are met, to a great extent, by the presentinvention, wherein in one aspect an apparatus is provided that in someembodiments combines various methods of die casting with semi-solidmetal in an efficient manner. There are, of course, additionalembodiments of the invention that will be described below and which willform the subject matter of the claims appended hereto.

Casting methods such as die casting, gravity permanent mold casting, andsqueeze casting have been used for Aluminum-Silicon (Al-Si) alloys. Inthixocasting semi-solid metal casting (SSM), specially prepared metalslugs are gradually brought to a semi-solid state, then transferred tothe casting machine, where a ram uses pressure to inject the SSM into adie. Once solidified, the die opens and the cast part is ejected. WithSSM, the viscosity is fairly high so the injection speed is lower thanwith conventional pressure die casting. This results in little or noturbulence, which reduces porosity. In rheocasting SSM, the SSM slurryis made from the liquid state. In an embodiment of the presentinvention, the rheocast SSM process is performed.

Die casting is a manufacturing process wherein a strong, durable andintricate product can be mass produced. Die casting is also referred toas high pressure casting and has the unique ability to transform rawmaterial into a finished form in the shortest possible cycle time. Oftenthe finished product requires no additional machining or otheroperations. Die cast products are also dimensionally stable. Die castingis an efficient, economical process allowing for a broad range ofgeometries, high speed production and closer tolerances that provideheat resistant, stronger products. Thin wall castings are stronger andlighter than products produced using other casting methods.

FIG. 1 is an illustration of an in-situ slurry formation apparatus 10according to an embodiment of the present invention. The in-situ slurryformation apparatus 10 is configured with and includes a funnel block12. The funnel block 12 includes a funnel 14, heaters 24, coolers 22 andtemperature sensors 26. The funnel 14 has generally a funnel shape withone end having a larger diameter than another end, although any othertype of configuration may be used. The funnel 14 is used to transportand cool a liquid metal from a liquid metal source to a die castingmachine. Liquid metal is poured into the funnel 14 at an inlet 16 andpasses through the funnel 14 through a metal flow path 18. The metalflow path 18 can be as long or short and have various turns as required,as long as it allows the liquid metal to cool down to a semi-solid metalstate or as close as desired by a user. As the metal passes through, itcools to SSM state, or near SSM state, and exits the funnel 14 at anoutlet 20.

The funnel 14 is maintained at a steady state temperature by using bothcoolers 22 and heaters 24 placed at various locations throughout thefunnel block 12. The coolers 22 are pathways in the funnel block 12whereby a cooling medium is passed. For example, oil, coolant or watermay be used as the cooling medium. Other types may also be used. Thecooling medium may flow through the passages or be contained staticallytherein.

The cooling passages may be combined with a water chiller that pumps andcools the cooling medium. Also, a re-circulatory system can be used topump water through and then provide a tower that allows the water tocool. If heaters are selected, they can be used in conjunction with acooling medium.

An alternative system may also be used to maintain the funnel 14 at asteady state temperature. A hot oil system offers similar capabilitiesas a water chiller. Also, an advantage of using hot oil instead of wateris that the hot oil may heat the funnel as well as cool it, eliminatingthe need for separate heaters. The hot oil may further maintain a higherset temperature than could be maintained with a water system. The hotoil system or water cooler/heater system may be used to heat or cool thefunnel as required by the user.

Heaters 24 may be cartridge heaters or any such heating device as may beappropriate. Temperature sensors 26 are placed in the funnel block 12 todetermine and regulate the temperature. The temperature sensors 26 maybe thermocouples or any such temperature sensor as may be convenient. Tokeep the temperature at a set range, thermocouples may be used in thesystem to monitor the temperatures.

These temperature sensors 26 send the temperature signal to a controller(not shown). This controller has a preset temperature range that is thedesired temperature range for the process. If the signal received fromthe temperature sensors 26 is below the range, the controller signals toa relay which will allow for power to run through the heaters 24 andheat the funnel block 12. If the temperature exceeds the range, thecontroller can be used to send a signal to the relay that opens andcloses a valve, letting the cooling medium run through the coolers 22.When the temperatures fall back inside the range, the heating or coolingmay be turned off. If the temperature is in the preset temperaturerange, no cooling or heating may be necessary. A similar process, usinga controller, would be followed if the hot oil system is used.

The funnel block 12 and the outlet 20 can be configured to mate withvarious die casting machines. Some examples of die casting machines arediscussed below, and are not limited to these machines. The size of thefunnel block 12 depends on the amount of metal to be poured through andthe amount of heat to be removed. For example, the funnel block 12 maybe approximately 7.375 inches tall, 10 inches wide and 11.5 inches inlength. The funnel block 12 dimensions may vary as necessary.

The funnel block 12 may be attached to the die casting machines usingmounting brackets or any such means as is desired and feasible. Thefunnel block 12 may also be welded to the die casting machine.

Aluminum adheres to steel and other metals and has a tendency to oxidizeand form a thin layer of oxidized aluminum upon contacting such metals.The layer of oxidized aluminum may flake off and enter the metal stream.Other contaminants may also enter the metal stream. To minimize oreliminate this problem, a non-wetting coating may be applied to theinside surface area of the funnel 14 to prevent oxide accumulation.There are several types of coatings that are available, for example,tungsten thermal coatings, boron nitride coatings and ceramic coatings.These coatings prevent the aluminum from oxidizing. To further preventmetal contamination, the funnel 14 may be separated at parting line withthe use of automation to allow for blow off. Other methods of preventingcontamination may also be used.

An embodiment of the presently claimed invention includes the in-situslurry formation apparatus 10 mounted to machines without the need tomodify the existing machines or change the layout to accommodate morespace than would otherwise be necessary. These machines also need not bereplaced with machines specially designed for SSM.

High pressure die casting (HPDC) at forces exceeding 4500 pounds persquare inch also allow for liquid metal squeeze casting and SSM diecasting. Squeeze casting is a method by which molten alloy is castwithout turbulence and gas entrapment at high pressure, to yield highquality, dense and treatable components. In contrast, SSM uses semisolid metal billets cast to provide dense heat treatable castings withlow porosity. Thus, products may be cast using either SSM casting orliquid metal squeeze casting.

Die casting produces complex shapes at lower costs. The use ofsemi-solid metal or liquid slurry metal as described herein overconventional molten metal reduces fluid turbulence when injected intothe die. In this manner, the amount of air that is sequestered withinthe final part is reduced. Less air in the final part lends greatermechanical integrity and allows cast products to be heat treated. Inaddition, metals that are SSM cast require less heat which reduces costand improves longevity of the molds and dies.

The microstructure of SSM cast products can determine the mechanicalproperties of the product. As such, the microstructure can bemanipulated to achieve desired results. One way to manipulate the finalmicrostructure of an SSM cast part is to control the time the metalremains in the SSM range. That is, the amount of time the metal spendsin the shot sleeve before it is injected into the molds can be regulatedor optimized for a desirable microstructure. Alternatively, molten metalat a predetermined temperature may be poured into the shot sleeve ofshuttle presses, i.e. presses that lack an indexing feature.

HPDC is a large volume, high productivity process for the production ofcomplex thin walled castings with part weights ranging from a few gramsto more than 15 kg. HPDC has been known for the production of housingsand other automotive front end structures and instrument panels.

The horizontal cold chamber die casting machine is the basis of the HPDCtechnology. In the cold chamber process, the metal reservoir isseparated from the injection system. The metal is filled into the steelcold chamber which is typically between 200 and 300° C. The typicalproduction cycle in the HPDC consists of leading metal into the coldchamber, moving the plunger and rapidly filling the die which dissipatesthe latent heat. During solidification, the casting is pressurizedhydraulically by the plunger to feed the solidification shrinkage.Locking forces up to 4000 tons are available to withstand the largepressures. The die is then opened and the cast product is ejected.

Hydraulic energy is provided by computerized systems that permit controlof metal, position, velocity and plunger acceleration to optimize theflow and the pressure during filling and solidification. The die cavitymay be evacuated to reduce air entrapment during die filling. Therefore,high integrity die casting can be produced by utilizing vacuum systems.Alternatively, SSM can be used to reduce turbulence. In conventional diecasting, the expertise of the foundry worker is critical to the finalcast product. Therefore, SSM takes the guess work out of casting andresults in a consistently high quality cast product.

A short die filling time and thin walls result in high cooling rates.This promotes a fine grain size which provides decent mechanicalproperties. The alloy itself is also very important. The alloycharacteristics must fulfill the necessary requirements of castabilitywhich involves higher fluidity, good feeding and low hot tearingtechnology.

HPDC also allows for rapid solidification and alloy flexibility in thatthe machines can accommodate hypoeutectic or hypereutectic alloys, thosecontaining less than 12.7% silicon or more than 12.7% silicon,respectively. HPDC also allows for a greater number of cavities per die.

FIG. 2 is an illustration of a HPDC die casting machine having thein-situ slurry formation apparatus 10 incorporated therein. The HPDCcasting cycle consists of a holding furnace 28 that retains the liquidmetal to be cast. A ladle (not shown) takes the metal and pours it intothe in-situ slurry formation apparatus 10, where the liquid metaltransforms into the SSM state. The SSM metal then exits the in-situslurry formation apparatus 10 into a pour hole 34. A hydraulic system 30then provides a shot cylinder 32 the ability to inject the SSM metalinto a die cavity 36.

The cold chamber 38 holds the liquid metal in place. The cold chamber 38in a HPDC machine is where the metal is poured in by the ladle from thefurnace before the metal is injected into the die. The metal istransferred from the furnace into the in-situ slurry formation apparatus10 and then the metal flows into the cold chamber 38. Once the metal isin the cold chamber, the metal will be injected into the die.

Die 40 are then moved forward by a platen 42 and the platen 42 is heldin place by tie bars 44 while the metal is cast. The platen 42reciprocating movement is controlled by clamping knuckles 46, closingand locking the die 40, maintaining adequate pressure, permitting themetal to solidify, opening the die 40 and ejecting the cast product. Theproduct may then be appropriately finished or sprayed.

FIG. 3 is a detailed representation of the in-situ slurry formationapparatus 10 configured for the HPDC machine 48 of FIG. 2. Inparticular, the funnel block 12 may be disposed over an injection sleeve50. Metal exiting the funnel 14 at the funnel exit 20 enters theinjection sleeve 50 at the injection sleeve inlet 52 and exits theinjection sleeve 50 at the injection sleeve outlet 54. The injectionsleeve inlet 52 may be associated with the pour hole 34 of FIG. 2.

The temperature of the molten metal entering the in-situ slurryformation apparatus 10 should be above the liquidus temperature for theparticular aluminum alloy in the furnace. For certain aluminum alloys,depending on the alloy chemistry, the metal temperature should be evenhigher than the liquidus to prevent sludge formation in the furnace.However, too much superheat (temperatures over the liquidus) allows formore hydrogen to enter the metal which leads to casting defects. Thehigher the superheat of the metal in the furnace, the more temperaturethe in-situ slurry formation apparatus 10 has to remove to get the metalin the SSM range. The metal temperature in the furnace needs to be aslow as possible but still be above the liquidus temperature. Thetemperature must also prevent any sludge particles from forming in theparticular alloy. Thus, the temperatures will vary with the particularalloy chemistry.

In-situ slurry formation apparatus 10 temperatures should be at atemperature that can be maintained at a steady state from cycle tocycle. This depends on the size of in-situ slurry formation apparatus 10and the amount of metal being poured through the in-situ slurryformation apparatus 10. This temperature will also be kept as low aspossible. However, the temperature should be high enough so the metalwill not solidify inside the in-situ slurry formation apparatus 10.Therefore, the temperature range may be in the range of 150 degreesFahrenheit to 500 degrees Fahrenheit. However, the ranges may vary basedon the in-situ slurry formation apparatus 10 size, metal chemistry andmetal quantity.

FIG. 4 is a representation of a Horizontal with Vertical ShotComponents, (HVSC) die casting machine 56 having the in-situ slurryformation apparatus 10 incorporated therein. The liquid metal iscontained in a holding furnace 58. A ladle (not shown) pours the liquidmetal from the holding furnace 58 into the in-situ slurry formationapparatus 10. The liquid metal is transformed into SSM state in thein-situ slurry formation apparatus 10. Then, a shot cylinder 60 tiltstowards the in-situ slurry formation apparatus 10 and the SSM metalenters the shot cylinder 60.

The shot cylinder 60 then tilts back to the original vertical position.The tilt-docking injection unit or shot cylinder 60 contains a separatedshot sleeve 64 for cooling and transfer. A hydraulic system 62 thenpushes the shot sleeve 64, enveloped by the shot cylinder 60, into thedie cavity 66, and the shot sleeve 64 deposits the SSM metal. A platen72 then moves die 68 and locks the die in place using tie bars 70.Clamping knuckles 74 allow the die 68 to open and close. Once the SSMmetal is cast, the cast product is ejected when the platen 72 movesback. Thus, HVSC machines contain horizontal die clamping with avertical, high pressure delivery system.

FIG. 5 is a detailed representation of the in-situ slurry formationapparatus 10 configured for the HVSC machine of FIG. 4. HVSC is ahorizontal clamping vertical shot chamber machine. The sleeve isvertical at a 15-20 degree angle and it fills up the tube at an angle.The liquid metal is transferred and poured into the funnel 14 where themetal flows through the funnel 14 undergoing conduction and heat loss.The metal exiting the funnel 14 is at SSM state and is then injectedinto the die, forming a cast product.

The in-situ slurry formation apparatus 10 is disposed over the injectionsleeve 64. The SSM metal exits the funnel block 12 at the funnel exit20, into the injection sleeve inlet 78 and exits the injection sleeve 64via the injection sleeve outlet 80. The injection sleeve 64 may beassociated with the shot cylinder 60 of FIG. 4.

Although the in-situ-slurry formation apparatus 10 is shown with HPDCand HVSC machines, one skilled in the art will recognize that anycasting machine in existence now or created later may easily beincorporated with the in-situ slurry formation apparatus 10, withoutbeing outside the scope of this invention.

FIG. 6 is an illustration of the microstructure obtained for a 356alloy. FIG. 7 is an illustration of the microstructure obtained for a206 alloy. A variety of metals and alloys may be used in thein-situ-slurry formation apparatus 10. However, the in-situ-slurryformation apparatus 10 may be particularly suitable for 356, 357, 206,380, 383, 390 alloys, as well as ADC-12 and 7XX series alloys.

In addition to providing SSM slurry and to achieving the desiredmicrostructure, the in-situ slurry formation apparatus 10 may also beused with liquid metal squeeze casting or conventional high pressure diecasting. The in-situ slurry formation apparatus 10 removes heat from theliquid metal as the metal flows through. This removal of heat lowers thetemperature of the metal and reduces cycle time. The lower temperatureof the metal permits it to solidify faster and increases the efficiencyof the process. Thus, the in-situ slurry formation apparatus 10 may beused to provide SSM slurry or lower temperature liquid metal squeezecasting for a variety of applications.

The present invention, therefore, easily allows existing machinery toaccommodate SSM without the need for costly capital equipment oradditional space in the plants. The in-situ slurry formation apparatus10 may be formed with a steel insert with copper and beryllium casings.In addition, it is highly wear resistant. The in-situ slurry formationapparatus 10 may also be fabricated from ANVILOY®, (Mallory AlloysGroup, St. Albans, England) which is a highly conductive steel.

ANVILOY® is a tungsten based material made using high temperature powdermetallurgy techniques. It was developed specifically for its hightemperature strength and excellent thermal conductivity. It is used inplace of lower conductivity high temperature tool steels. A benefit ofANVILOY® is its simplicity of tool manufacture i.e., no heat treatment,low erosion and excellent resistance to thermal cracking. This allowsfor ANVILOY® to replace H-13 steel. High thermal conductivity allowsincreased cooling rates in difficult to cool areas of a die casting andhas the potential to increase production rates. ANVILOY® can be easilymachined and can be repair welded.

Some of the benefits of ANVILOY® include minimal thermal fatigue,minimal soldering, low erosion, and accelerated cooling. ANVILOY® may beeasily machined and worn parts are easy to remachine into smallerdiameter core pins. ANVILOY® may be easily welded and repaired andrequires no heat treatment before or after machining.

The many features and advantages of the invention are apparent from thedetailed specification, and thus, it is intended by the appended claimsto cover all such features and advantages of the invention which fallwithin the true spirit and scope of the invention. Further, sincenumerous modifications and variations will readily occur to thoseskilled in the art, it is not desired to limit the invention to theexact construction and operation illustrated and described, andaccordingly, all suitable modifications and equivalents may be resortedto, falling within the scope of the invention.

1. An apparatus for converting molten metal to semi-solid metalcomprising: a conduit having an inlet and an outlet to transport themolten metal; and a temperature regulator disposed adjacent the conduitto regulate the temperature of the molten metal; and a housingsurrounding the conduit and the temperature regulator.
 2. The apparatusof claim 1, wherein the temperature regulator further comprises aheater, a cooler and a temperature sensor, operably coupled to acontroller.
 3. The apparatus of claim 1, wherein the temperatureregulator further comprises a hot oil system and a temperature sensoroperably coupled to a controller.
 4. The apparatus of claim 3, whereinthe hot oil system is configured to heat and cool the conduit.
 5. Theapparatus of claim 1, wherein the conduit has a funnel shape.
 6. Theapparatus of claim 5, wherein the funnel comprises a first end having afirst diameter, a second end having a second diameter and a pathdisposed between the first and second ends, wherein the first diameteris larger than the second diameter, and wherein the path has anon-linear configuration.
 7. The apparatus of claim 1, wherein theconduit has a length configured to cool molten metal to semi-solidmetal.
 8. The apparatus of claim 1, wherein the housing is configured tocouple to a die casting machine.
 9. The apparatus of claim 1, whereinthe conduit further comprises a non-wetting coating on an inside surfaceof the conduit.
 10. The apparatus of claim 9, wherein the non-wettingcoating further comprises a tungsten thermal coating, a boron nitridecoating or a ceramic coating.
 11. The apparatus of claim 1, wherein theoutlet is coupled to a die casting machine inlet.
 12. The apparatus ofclaim 1, wherein the apparatus is configured to couple to a highpressure die casting (HPDC) machine.
 13. The apparatus of claim 1,wherein the apparatus is configured to couple to a horizontal withvertical shot components (HVSC) die casting machine.
 14. The apparatusof claim 1, wherein the apparatus is configured to convert molten metal206, 356, 357, 380, 383, 390, ADC-12 and 7XX alloys to semi-solid metal.15. The apparatus of claim 1, wherein the conduit further comprises athermally conductive material.
 16. The apparatus of claim 15, whereinthe conduit further comprises a steel insert with copper and berylliumcasings.
 17. The apparatus of claim 15, wherein the conduit furthercomprises tungsten.
 18. A method for converting molten metal tosemi-solid metal comprising: coupling a conduit to a die castingmachine, wherein the conduit comprises an inlet, an outlet and a bodydisposed between the inlet and the outlet; regulating the conduit'stemperature; surrounding the conduit with a housing; inserting moltenmetal at the inlet; cooling the molten metal to semi-solid metal in thebody; and expelling semi-solid metal from the outlet.
 19. The method ofclaim 18, wherein the step of regulating the temperature of the conduitis done through a heater, a cooler and a temperature sensor operablycoupled to a controller.
 20. The method of claim 19, wherein the step ofregulating the temperature of the conduit is done through a hot oilsystem and a temperature sensor operably coupled to a controller. 21.The method of claim 18, wherein the body has a non-linear configuration.22. The method of claim 18, wherein the conduit comprises a thermallyconductive material.
 23. The method of claim 18, wherein the conduitcomprises a non-wetting coating to prevent the oxidation of aluminum.24. The method of claim 18, wherein the conduit has a funnel shape. 25.A system for converting molten metal to semi-solid metal comprising:means for coupling a conduit to a die casting machine, wherein theconduit comprises an inlet, an outlet and a body disposed between theinlet and the outlet; means for regulating the conduit's temperature;means for surrounding the conduit with a housing; and means for coolingthe molten metal to semi-solid metal in the body.
 26. The system ofclaim 25, wherein the means of regulating the temperature of the conduitis done through a heater, a cooler and a temperature sensor operablycoupled to a controller.
 27. The system of claim 25, wherein the step ofregulating the temperature of the conduit is done through a hot oilsystem and a temperature sensor operably coupled to a controller. 28.The system of claim 25, wherein the body has a non-linear configuration.